|Year : 2016 | Volume
| Issue : 3 | Page : 199-200
Templates for the corneal surgeon
Department of Ophthalmology, Amrita Institute of Medical Sciences, Kochi, Kerala, India
|Date of Web Publication||2-May-2017|
Dr. Anil Radhakrishnan
Department of Ophthalmology, Amrita Institute of Medical Sciences, Kochi - 682 041, Kerala
Source of Support: None, Conflict of Interest: None
Patch grafting is a procedure employed to address large corneoscleral perforations or impending ones where tectonic stability of the globe is at stake. It is usually done using corneal trephines, the size of which depends on the largest dimension of corneal pathology, often necessitating a large area of dissection. Instead of trephination to ensure the right fit of the excised tissue, we thought that templates made from surgical drape can serve a similar purpose, which is exemplified in this article.
Keywords: Patch graft, surgical drape, template
|How to cite this article:|
Radhakrishnan A. Templates for the corneal surgeon. Kerala J Ophthalmol 2016;28:199-200
Patch grafting is done for large corneal perforations, more than 3 mm, which are unlikely to be sealed by cyanoacrylate glue. In a patch graft, as the name suggests, only a small patch of cornea is replaced unlike conventional keratoplasty., It is only a temporary measure, and is usually curative for a peripheral corneal perforation; it is a temporizing measure for a pathology involving visual axis. A typical scenario for a patch graft would be sterile corneal melt following rheumatoid arthritis or other connective tissue disorders. Another instance would be a localized corneal infection with poor response to medical therapy, for example, a wound infection following cataract surgery. Rarely, corneal thinning disorders, such as Terrien's marginal degeneration, also demand the use of a patch graft.
Conventionally, corneal trephines are employed for patch grafts, the size of which depends on the largest dimension of corneal pathology. For small localized perforations, dermatological trephines can be used. However, if the circumferential extent of the pathology is large, for example 7 or 8 mm, similarly-sized corneal trephines have to be employed, which necessitates a greater area of dissection both to the corneal and scleral side. More the encroachment towards central cornea, more the effect on vision. Further, a corneal graft covering the sclera can be quite a cosmetic blemish.
Freehand dissection instead can limit the area of tissue replacement, however, it is surgically demanding. Tissue distortion and wound leak can occur, even if there is a small mismatch. Hence, many surgeons use corneal trephines of different size for marking inner and outer boudary of dissection, however, it has a high margin of error.
We thought that the exact reproduction of the area to be replaced with the help of templates could be an easy option. Templates made by artists are used for exact reproduction of a pattern in different industries. Similar templates fashioned from surgical drape or any similar material can be custom-shaped depending on the size and shape of pathology. In the medical field also, templates are rarely employed by plastic surgeons.,
Use of templates appears to be a cost-effective method for patch grafting which can minimize the amount of tissue replaced [Figure 1] and [Figure 2].
|Figure 1: (a) A 50-year-old lady had PUK secondary to Wegener's granulomatosis and was left with an area of extreme corneal thinning. (b) The area planned for lamellar patch graft marked and a template is made from surgical drape. (c) Template made from surgical drape kept on the donor corneoscleral button. (d) Corneoscleral tissue shaped exactly as the template sutured – immediate postoperative picture, (e) 1-year postoperative picture|
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|Figure 2: (a) A case of necrotising scleritis with secondary bacterial infection in Wegener's granulomatosis. (b) Patient left with severe scleral thinning and ectasia after good control of infection and adequate immunosuppression; (c) template of scleral patch graft made with surgical drape; (d) custom-shaped scleral graft being sutured; (e) 1-month postoperative picture|
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Vanathi M, Sharma N, Titiyal JS, Tandon R, Vajpayee RB. Tectonic grafts for corneal thinning and perforations. Cornea 2002;21:792-7.
Soong HK, Farjo AA, Katz D, Meyer RF, Sugar A. Lamellar corneal patch grafts in the management of corneal melting. Cornea 2000;19:126-34.
Matros E, Santamaria E, Cordeiro PG. Standardized templates for shaping the fibula free flap in mandible reconstruction. J Reconstr Microsurg 2013;29:619-22.
Tregaskiss A, Vermaak PV, Boulton R, Morris RJ. The template technique for breast mound planning when using abdominal flaps for breast reconstruction. Breast 2012;21:686-9.
[Figure 1], [Figure 2]